1. Field of the Invention
The present invention relates to a method of assembling rails and sleepers, the assembly being carried out with different degrees of resilient softness. The invention also concerns a track for trackbound vehicles, where rails and sleepers are assembled with different degrees of resilient softness.
2. Description of Background Art
When a train moves along a railway track, large amounts of energy are released. Part of the released energy is spread as noise from the train, down into the ground, out in the air and into and along the track. This noise, of course, causes serious problems in built-up areas. Attempts are usually made to obviate these problems by means of embankments or other types of noise protection, which are costly.
Attempts have also been made to solve the problem of noise by assembling rails and sleepers with more or less resilient softness. The resilient softness is determined by the properties of the elastic rail seat which is positioned between the rail base and sleeper and which usually consists of two steel plates with a rubber portion therebetween. The resilience is determined by the quality of the rubber. Assembly with little resilient softness causes attenuation of the noise in the track, but not out in the air and down into the ground, whereas assembly with great resilient softness causes attenuation of the noise out in the air and down into the ground but hardly along the track, insofar as the noise effect directed along the rail is released in the first discontinuity in the rail, resulting in noise in this position. Finally, rails and sleepers have been assembled with alternatingly great and little resilient softness. In fact, this results in the energy released by the train being distributed in a somewhat more uniform manner to the surroundings, but this is also no satisfactory solution to the noise problem.